A COMPARATIVE STUDY OF THE FOUR OF PADDY STEM-BORERS BELONGING TO THE GENERA CH:ILOTRAEA AND IN ASIA (: : CRAMBINAE)*

BY V. P. RAO (Entomologist-in-Charge) AND H. NAGARAJA (Entomological Assistant) (Commonwealth Institute of Biological Control, Indian Station, Bangalore, India) (Received July 1, 1965)

INTRODUCTION

STUDIES have been carried out by a number of authors to describe various striped -borers attacking sugarcane, paddy and other graminaceous crops. Earlier workers based their studies on the general eolour pattern of the wing and body of the , structure of the pupae and the coloured stripes on the body and arrangements of crochets in the prolegs of the cater- pillars. The later workers in addition to the above-mentioned characteristics made a study of the wing venation, genitalia of male and female molhs and ehaetotaxy of the caterpillars.

Fletcher and Ghosh 0920), Ghosh (1921) and Fletcher (1928) based their classification of the graminaceous borers recorded by them in India on the colour pattern and the shape of the wing, body, palpi, etc., of the moths, structure of the pupae and the body colour, stripes and arrangement of crochets in the prolegs of the caterpillars. Kinoshita and Kawada (1932) showed the difference between Chilo simplex Butler and Chilo zonellus (Swinhoe) [now known under the names, Chilo suppressaHs (Walker) and Chilo partellus (Swinhoe) respectively] comparing the chaetotaxy of the head capsule and genitalia of these two species. Isaac and Rao (1941) gave

* This research has been financed in part by a grant made by the United States Department of Agriculture under PL-480. m 175 176 V.P. RAO AND H. NAGARAJA an account of the chaototaxy of the known lepidopterous borers on sugarcane in India and included a key for their identification, while Isaac and Venkat- raman (194!) described the pupae of these borers. Trehan and Butani (1948) discussed the systematic position of Chile partellus (formerly known as C. zonellus) and gave an account of the chaetotaxy of the larva. Kapur (1950) described the common Crambid borers in India, added detailed descriptions of the wing venation of the different:common genera, male and female genitalia and erected the new germs Chilotraea different from Chile in having the irons produced forward but subrounded and Sc and R1 fused in the forewing. Butani (1956) using characters which can easily be made out by using hand lens, such as body colour, stripes, arrangements of crochets in the prolegs and spiracles, published a note on their identification. Nair (1958) in his study of biology and control of Chilotraea polychrysa (Meyrick) [formerly known as Proceras polychrysa (Meyrick)] described the colouration of the stripes and the arrangements of crochets in the caterpillar and in some. what detail the pupal morphology. Gupta (1938 and 1960) made a compara- tive study of the common species of striped Crambid borers on sugarcane basing the differentiation on the shape and colour of moths, chaetotaxy of the caterpillars, structure of the pupae, wing venation and genitalia of both sexes. Bleszynski and Collins (1962) recently considered the genus Chilotraea of Kapur as a synonym of the genus Chile and included in it the species Chile auricilia, C. partelhts, C. polychrysa and C. suppressalis amongst the well-known borers of paddy. But they did not give any reasons for synonymyzing the genus Chilotraea with the genus Chile. In the present paper, therefore, tile genus Chilotraea has been retained by the authors. Fracker (1915) earlier showed the importance of the study of chaetotaxy in differen tinting the caterpillars using Greek alphabets for the nomenclature of the setae. Later Peterson (1959) published his volumes on "Larvae of " using Fracker's terminology for the setae of Lepidopterous larvae. Although a few borers attacking sugarcane and other graminaceous crops also feed on paddy stem and the above-mentioned stuclies on sugarcane borers are useful, a careful comprehensive study of the chaetotaxy of all the striped borers attacking paddy, the structure of their pupae, the wing venation and genitalia of the moths has not been made so far. As a result of this, there is a confusion in the identity of the striped moth-borers attacking paddy. The present authors, therefore, made a detailed comparative study of the borers, pupae, wing venation and genitalia of the species, Chilotraea auricilia (Dudgeon), Chilotraea polychrysa 0VIeyrick), Chile suppressalis (Walker) and Chile partellus (Swinhoe). The results of the observations made a re given in this paper along with keys and charts prepared for the Four Species of Paddy Stem-Borers in Asia 177 identity of the different species of borers. Nomenclature of the chaetotaxy of the head and body of caterpillars has been adopted after Peterson (1959) and Fracker (1915) respectively, wing venation after Comstoek and Needham (1898 and 1899) and genitalia after Kapur (1950) and Jepson (1954). Termi- nology of female genitalia has been adopted after Tuxen (1956) while for the convenience of the study of the spines on the upper half of eremaster of the pupa a fresh nomenclature has been suggested.

TECHNIQUE AND MATERIALS EMPLOYED For the study of the chaetotaxy, caterpillars were cleared in 10~o KOH, dehydrated in glacial acetic acid, passed into carboxylol, clove oil and xylol and mounted in Canada-balsam. About 8-12 fully grown caterpillars were mounted and several unmounted preserved and live specimens of each species were examined. No staining was necessary as the tubercles and setae were quite distinct enough for the study., For the genitalia, mounts were prepared in the same way. The genitalia were stained with acid fuchsin stain so as to observe the delicate membranous parts like bursa copulatrix, etc. The wings were treated with 10~o KOH alld the scales brushed off carefully and upgraded to 70~ alcohol, stained in eosin dissolved in 70~ alcohol and again upgraded to absolute alcohol. The wings were then passed through clove oil and xylol and later mounted in Canada-balsam. About 12-16 specimens of both fore and hindwings of each species were mounted. Sketches were made of pupal structure and of the caterpillars showing stripes and camera-lucida sketches were made to show chaetotaxy, wing venation and genitalia.

SPECIES OF STRIPED STEM-BORERS ATTACKIN~ PADDY IN ASIA Observations made by the authors have shown the occurrence of four species of striped stem-borers attacking paddy in India. They are: (1) Chilotraea auricilia (Dudgeon), (2) Chilotraea polychrysa (Meyrick), (3) Chilo suppressalis (Walker) and (4) Chilo partellus (Swinhoe). Key for the separation of the two genera Chilotraea and Chilo is given below:-- . Frons produced forward and conical with a corneous point at the apex . 2 Frons produced, smooth, subround without a eorneous point (except in some specimens of C. auricilia where a minute to very minute point is present) ..... 3 178 V.P. RAo AND H. NAGARAJA

2. Sc and R1 run separately Chilo Zincken 3. Sc and R1 fused for some distance. Chilotraea Kapur

DESCRIPTION OF THE DIFFERENT SPECIES

1. Chilotraea auricilia (Dudgeon) Dudgeon (1905) included his original description of this species under the name Chilo auricilia and gave a brief account of the wings of the male and female moths. Kaput (1950) placed this species in the new genus Chilotraea erected by him and included an account of the moth and the geni- talia. Gupta (1938, 1960) gave a detailed account of the chaetotaxy of the caterpillar, the pupal structure, the general colouration of the moth and the genitalia of male and female and described the species under the names attricilia (Ddgn.) in 1938 and Chilotraea auricilia (Ddgn.) in 1960.

Larva Cream to dull ochre in colour; head dark fuscous, body with 5 violet stripes the lateral stripes passing above the abdominal spiracles (Fig. 5). Abdominal crochets approximately triordinal towards the meson and practically uniordinal on the lateral side (Fig. 9) [Gupta (1960) considered them as biordinal]. Chaetotaxy of the head with the position of Pa almost in a line drawn on PI and L1 ; Pb slightly outside the line drawn on P1 and P2; A2 comparatively shorter; Adfa very near to Adf2 (Fig. 13). Tubercle beating Kappa group in first thoracic segment (TI) not showing constriction between kappa and eta. Body with epsilon partly associated with rho in the first abdominal segment (A1) (Fig. 25) [Gupta (1960) erroneously stated that epsilon is separate from rho]; lines drawn on setae alpha and beta con- verge cephalad on A8; rho situated above and cephalad of the spiracle on A8 (Fig. 29).

Pupa

Genae and thoracic spiracles projecting; Irons normal; anterior region of the dorsum of each of the 5th, 6th and 7tb abdominal segments with dis- tinct spines (Fig. 33) arranged in a row along with a few minute spines above the row (Fig. 37) ; cremaster with 3 pairs of dorsal and one pair of ventral broad spines [Gupta (1960) observed only two pointed projections]; the postero-lateral and postero-dorsal spines either larger than or equal to the postero-ventral spines (Figs. 46 and 47). Four Species of Paddy Stem.Borers in Asia 179 Wing Venation Forewing with apex slightly pointed, Se and R1 fused together for some distance (Fig. 54). Hindwing with apex pointed, inner margin normal; M1 arising from Rs on a short stalk after the anterior angle of the discoidal cell; M2 and M3 arising on a common short stalk (Fig. 58). Genitalia c~. Harpe subquadrate; vinculum narrow, triangular; anellus with median membranous plate with lateral chitinized blunt lobes; aedeagus bifurcate, upper limb with a pointed projection situated dorsally in the middle, the apex being pointed and the lower limb tongue-like, bifid at the apex (Figs. 62, 66 and 68). 9. Signum absent; bursa copulatrix short, slightly capitate ; lamella antevaginalis semicircular wrinkled above the ostium bursae; lamella post- vaginalis distinct but small (Fig. 78).

Distribution (i) India.--Borers of this species have been recorded by the authors in India on paddy at Gauhati, Jorhat, Kamalpur, Kauseria and Shillong in Assam ; Kalimpong and Chandallnagar in West Bengal ; Sabour in Bihar; Bardoli in Gujarat; Katua in Jammu and Kashmir and Bhubaneswar in Orissa. The caterpillars were also recorded on sugarcane at Lucknow in Uttar Pradesh; on maize at Kalimpong in West Bengal. Earlier records were made on juar (Fletcher and Ghosh, 1920) and on sugarcane (Kapur, 1950). (ii) Other Countries.--This species has also been recorded in Burma, Ceylon and Taiwan (Jepson, 1954).

2. Chilotraea polychrysa (Meyrick) Meyriek (1932) originally described the species under the name Diatraea polychrysa from Malaya. Nair referred to the o~urrence of this species for the first time from India in 1958 and included an account of the borer, moth and pupa. Larva General colouration, stripes and crochets are as in Chilotraea auricilia. Chaetotaxy of the head with position of Pa slightly below the. line drawn on P1 and L1 ; Pb outside the line drawn on P1 and P2; A2 very minute ; Adfa 180 V. P. RAO AND H. NAGARA/A

TABLE Tabular statement showing the differences in the stripes and chaetotaxy Chilo attacking

Name of the Stripes . Cro~ets on the prolegs Head borer (Figs. 1-8) (Figs. 9-12) (Figs. lS-16)

Five violet stfipe~ lateral Chilotrawa stripes pass ,above abdo- Uniserial, almost trioz~li- Position o[~b outside the aurldlia Iminai spiracles nal, arranged in a com- line drawn on P! and P2; (Dudgeon) plete circle Paalmost on the line drawn on PI and L1, Adla very near to Adf2~ A2 shorter

Cs}ilotrasa Position of Pb distinctly ye~r'~sa outside the line drawn Meyrick ) on P! and P2; Pa slightly below the line drawn on PI and LI; Adfa very near to Adf2; A2 minute

CMlo su~rtv Five complete and two Uaiserial, almost triordi- Position of Pb on the line salis (Walker) incomplete and broken nai, arranged in com- drawn on PI and P2; Pa violet "stripes ; lateral plete circle; but lateral slightly below the line stripes pass on the abdo- crochets are not close drawn on PI and L1; minal spiracles; the sub- sometimes giving an Adia very near to lateral broken stripes appearance of incomplete Adf2; A2 longer pass on Kappa groups circle on the abdominal seg- ments

C~ilo ~arttllut Four pinkishstripe.vj late- Uniserlgl, almost triordi. Position of Pb on tile (Swinho~) ral stripes pass above nal, arranged in a com- line drawn on P! and splmcles on abdominal plete ~-cle P2; Pa on the line segments drawn on Pl and L1; Adfa almost midway between Adfl and Ad[2; A2 longer vory near to Adf2 (Fig. 14). This spccios differs from C. auricifia in having tho tuber¢lo bearing Kappa group in T1 slightly constricted in between kappa Four Species of Paddy Stem-Borers in Asia 181 I of the four species of borers belonging to the genera Chilotrae and paddy in Asia

I Thoracic segment II Thoracic segmentI I Abdominal segment VIII Abdominal segment (Figs. 17-20) ( Figs. 21-24) (Figs. 25-28) (Figs. 29.32)

Position of the Kappa Normal Epsilon partly associa- Lines drown through group normal, without ted with rho setae alpha and beta any constriction bet- converge cephalad ; ween kappa and eta rho set above and cephalad to the spira- cle

Position of the Kappa Epsilon wholly aJsocia- Lines drawn through group normal, but the ted with rho setae alpha and beta tllbmv.le bearing Kappa converge eaudad; rho group shows a slight setabove and cephalad constriction in between to the spiracle kappa and eta

Kappa group a little Epsilon separate from Alpha and beta are ¢ephalad to the verti- rho almost at equal dis- cal line of the spiracle tance from meson; rho situated just oppo- site to spiracle

Presence of asetose Epsilon separate from tubercle In b~ween rho. Presence of theta and Pi group asetose tubercle be- one in each of me.so hind spiracle on each and metathorax abdominal segment from A 1-7 inclusive

and eta (Fig. 18); opsilon in A1 wholly associated with rho (Fig. 26); lines drawn through the sotae alpha and beta converging caudad on, A8 (Fig. 30). 182 V. ]:). RAO AND H. NAGARA.)A

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TABLE Tabular statement showing the differences in genitalia of the moths and Chilo attacking

Male Ge~ta~a Name of the borer Harpe Vinculum An~lus Aedeagus

CMlotfaea Subquadmte Narrow, tri- With median mem- Bifurcate, upper limb with a auridlia (Fig. 62, h) angular branous plate with pointed projection situated (Fig. 62, ~) sclerotized blunt dorsally in the middle, the (Dudgeon) lateral projections apex being pointed and the (r~g, 68) low& limb tongue-like, the apex bifid (Fig. SS)

C/dlotrata Broadly tri- With trun- Highly chitinized, Tr~nrcat~, upper limb pointed ~olychryza angular cated base erescent shaped with swollen middle, lower (Mey~ck) (F~. 65, h) {Fig. 63, ~) (~g. eg) limbs U-shaped with blunt and sllghtly dilated tips with cornuti (Fig. IF/)

~'lo :uppres- Elongated and U-shaped Without a median Bifurcate for about 2/3 of its zali$ ~ iangu ISn't, (Fig. 64, v) plate, the lateral length, the upper limb with- (Walker) the ventral arms broadly enlar- out a sharp apex, shape more margin being ged each with two cylindrical; the lower limb more convex lobes, the inner lobe slender with ¢lavate tip, the drawn into a long cornuti present on the inner blunt process margin (Fig. 74) (Fig. 72)

Chila #artel- Apex blunt Broadly with highly cbiti. BifercAte for about 2/3 of the lus with a blunt V-shaped nized ~Imost tri- length, upper limb with poin- (Swinhoe) proje c t i on (Fig, 65, v) angular median plate ted apex and ventral triangu- near the base with long lateral lar keel in the middle. The of the costa processes lower limb with clavate tip, (~. s~.~) having comuli Oqg. 7J) {~g. 73) Four Species of Paddy Stem.Borers in Asia 185 IV of four species of borers belonging to the genera Chilotraea paddy in Asia

Female Genitalia Name of the borer Lamella post- I Lamella antevaginalis vaginalis Bursa eolmlatriz Signum

7Mtotraea In the form of semi- Di stin c t, but Slightly capitate Absent auricilia circular wrinkled small (Fig. 78) (Fig. 78) (Dudgeon) scleflte surrounding (Fig. 78) ostium bursae (Fig. 78)

?~ilotr~a In the form of small Indistinct Clavate Absent poZyc~rysa projected chitinized (Fig. 79) (Fig. ";9) {~g. 79) (Meydck) piece broader than long

~tlo suppres* Not distinct, in the Indistinct with Ostlum bursae slightly Present; large $~Zi$ form of semicircular! very indistinct enlargedt ductus bursae I with hook- (Walker) p o o r I y chitinized wrinkles enlarged, uniformly thinly i like sclero- area above ostium (Fig. 80) sclerotized with longi- tized minute bursae tudinal wdnkl~; corpus bodies (Fig. 80) bursae clavate; the region (Fig. 80) in between ¢~iarged duc- tus bursae and corpus bursae narrow and slea- dar (Fig. 80)

ff]dlo partd- Large plate-likewith Indistinct Comparatively long, capi- Present, small Ix longitudinal wrin- (Fig. 81) rate, ductus bursae (Fig. 81) (Swinhoe) kles with bifid apex ns.rrow (Fig. 81) 186 V.P. RAO AND H. NAt~A~IA

Pupa General shape and eolour same as in Chilotraea auricilia. Difference occurs mainly in the cremaster. The postero-ventral spines are large and prominent and postero-lateral and postero-dorsal spines are less prominent (Figs. 48 and 49). The arrangemem of spines on the anterior region of thc dorsum of 5th, 6th and 7th abdominal segments almost similar to that of C. auricilia except for the presence of more minute and very minute spines above the row of the distinct spines (Fig. 38).

Wing Venation Forewing as in C. auricilia with the apex slightly blunt (Fig. 55). Hind- wing with apex slightly blunt, inner margin normal; M1 arising from Rs at the point of the anterior angle of the discoidal cell ; basal areole normal; M2 and M3 arising on a long common stalk (Fig. 59).

Genitalia ~. Harpe broadly triangular; vinculum with truncated base (Fig. 63); anellus highly chitinized, crescent-shaped (Fig. 69); aedeagus trifurcate, upper limb pointed with swollen middle, the lower limbs U-shaped with blunt and slightly dilated tips covered with cornuti (Fig. 67). ~. Signum absent; bursa copulatrix comparatively short and clavale, base of ductus bursae chitinized; lamella antevaginalis in the form of small projected chitinized piece broader than long, lamella postvaginalis indistinct (Fig. 79).

Distribution (i) India.--The borers of this species have been recorded by the authors exclusively on paddy at Kamalpur in Assam; Kalimpong and Chandannagar in West Bengal; Palghat and Trivandrum in Kerala; Kudikapalyam in Madras and Bhubaneswar in Orissa. (ii) This species has also been recorded in Java and Malaya (Jepson, 1954). 3. Chilo suppressalis (Walker) Original description of this species by Walker (1863) was under the name suppressalis. Description of the moth and the caterpillar including an account of stripes and crochets was made by Fletcher and Ghosh (1920) and Kapur (1950) described the moth and genitalia of male and female. Four Species of Paddy Stem-Borers in Asia 187 Larva Dull yellow coloured ; head, prothoracie shield and mid-dorsal tubercles of meso and metathorax are ochreous; with 5 distinct (one median, two subdorsal and two lateral) and 2 indistinct sublateral stripes, subdorsal slripes very broad, the lateral stripes pass on the spiracles, the broken indistinct sublateral stripes pass on the Kappa groups of the abdominal segments (Fig. 7). Crochets almost triordinal towards the meson and almost uniordinal towards the lateral side, forming almost complete circle, sometimes giving an appearance of incomplete circle due to the sparse arrangement of tiny lateral crochets (Fig. 11). Head with position of Pa slightly below the line drawn on P1 and L1 ; Pb on the line drawn on PI and P2; A2 comparatively long; Adfa very near to Adf2 (Fig. 15). Kappa group in prothorax slightly cephalad to the vertical lille of the spiracle (Fig. 19). Epsilon separate from rho in AI (Fig. 27); rho opposite to the spiracle in A8 (Fig. 31).

Pupa Head with frons produced forward; gcnae not projecting; lhoracic spiracles slightly elevated; anterior region of the dorsum of 5th, 6th and 7th abdominal segments shagreened but without spines (Figs. 39 and 43); cremaster bearing one or two pairs of setae, with only postcro-lateral and postero-dorsal spines which are not as distinct as in lhe other three species (Figs. 50 and 51).

Wing Venation Forewing with apex blunt; Sc and RI run separately; anterior angle of the discoidal cell almost in line with the posterior an~le (Fig. 56). Hind- wing with blunt apex; inner margin more enlarged; M1 arising from Rs after the anterior angle of the cell on a short stalk ; basal areole larger ; M2 and M3 arise almost at a point from the posterior angle of the discoidal cell (Fig. 60).

Genitalia ~. Harpe elongated and triangular; the ventral margin being more convex; vinculum U-shaped (Fig. 64); anellus without a median plate, the lateral arms broadly enlarged each with two lobes, the inner lobe drawn into a long blunt projection (Fig. 74); aedeagus bifurcate for about ~ of its length, the upper limb more cylindrical without a sharp apex, the lower limb slender with clavate tip and with cornuti present on the inner margin (Fig. 72). 188 V.P. 17o,o AND H. NAGARAJA

~. Signum present, very large with hook-like chitinized bodies; bursa copulatrix with duetus bursae enlarged, uniformly ch.itinized and longitudinally wrinkled; corpus bursae clavate, the region in between the enlarged ductus bursae and corpus bursae narrow and slender ; ostium bursae slightly enlarged. Lamella .antevaginalis not distinct, in the form of semiciicular poorly chitinized area above ostium bursae; lameUa postvaginalis very indistinct (Fig. 80).

Distribution (i) India.--This species has been recorded by the authors exclusively on paddy at Gauhati, Jorhat and Kamalpur in Assam; Kalimpong in West Bengal; Sabour in Bihar and Sambalpur in Orissa. Earlier records of this species were by Fletcher and Ghosb (1920) ufider the name rice chile at Pusa in Bihar. (ii) C. suppressalishas been recorded also in China, Hawaii, Indonesia, Japan, Korea, Malaya, Philippines, Taiwan (Jepson, 1954), Thailand and South Vietnam.

4. Chile partellus (Swinhoe) The two species Chile zonellus and Chile partellus described originally under the genus Crambus by Swinhoe in 1884 and 1885 respectively have been considered as synonyms by Kapur (1950). Bleszynski and Collins (1962) while agreeing to the synonymy have used the name C. partellus as zonellus was stated to be preoccupied. Descriptions of moth, genitalia and wing venation were made by Kapur (1950) while Gupta (1960) described wing venation and genitalia of the moth. chaetotaxy of the caterpillar and pupal structure. Larva It can be differentiated from the other three species in having only 4 pinkish stripes (Fig. 4), the median stripe being absent, the lateral stripes passing above the abdominal spiracles (Fig. 8). Head with position of Pa on the line drawn on P1 and L1 ; Pb on the line drawn on P1 and P2 ; A2 comparatively long; Adfa almost midway between Adfl and Adf2--this character is distinct from the other three species (Fig. 16). It can also be differentiated from the other species in having asetose tubercles one in each of meso and metathorax in between theta and Pi group (Fig. 24) and one in each of the abdominal segments 1-7 inclusive, behind the spiracle (Fig. 28); arrangement of crochets almost triordinal towards the meson and almost Four Species of Paddy Stem-Borers in Asia 189 uni or biordinal towards lateral side, forming a complete circle; rho in A8 situated before the spiracles (Fig. 32) [This fact has not been mentioned by Gupta (1938, 1960)]. Pupa Frons blumly projected, genae slightly projecting; thoracic spiracles slightly projecting. The shape and arrangement of spines on the anterior region of the dorsum of 5th, 6th and 7th abdominal segments are different from Chilotraea auricilia; the spines being very minute, innumerable and intricately arranged sometimes giving an appearance of thick dorsal spiny bands (Figs. 36 arid 40). Cremaster with 3 pairs of dorsal and one pair of ventral broad spines; all arc equal in size (Figs. 52 and 53). Wing Venation Forewing with apex sharply pointed ; Sc and R1 run separately, posterior angle of the discoidal cell being slightly distad (Fig. 57). Hindwing with apex slightly pointed, inner margin normal; MI arising from Rs within the area of the cell, basal areole normal; M2 and M3 never arise on a short stalk [as mentioned by Gupta, 1960)] but arise separately from the posterior angle of the discoidal cell (Fig. 61). Genitalia d. Harpe with blunt apex and with a blunt projection near the base of the costa; vinculum broadly V-shaped (Fig. 65); anellus with highly chitinized almost 'triangular median plate with lateral processes (Fig. 75); aedeagus bifurcate fcr about ~ of the length, upper limb with pointed apex and with a ventral triangular keel in the middle, the lcwer limb slender with clavate head havirtg cornuti (Fig. 73). ~. Sigrmm present but very small ; bursa copulatrix very long, capitate ductus bursae narrow, not well defined. Lamella antevaginalis very distinct in the form of large plate having longitudinal wrinkles, bifid posteriorly above the ostium bursae; lamella postvaginalis not distinct (Fig. 81).

Distribution (i) India.--Caterpillars of this species have been recorded by the authors on paddy at Gauhati and Kauseria in Assam; Burdwan, Chandannagar, Kalimpong, Plassey and Ramnagar in West Bengal; Sabour in Bihar and Bhubaneswar in Orissa. Caterpillars were also recorded onjuar at Mahadana- puram in Madras, Bodhan in Andhra Pradesh, Sabour in Bihar, Ranibennur 190 V.P. RAO AND H. NAGARAJA and Tumkur in Mysore; on maize at Kalimpong in West Bengal, Kolhapur in Maharashtra and Dalhousie in Punjab. Earlier records were made on sugarcane (Kapur, 1950), on 'sama' (Panicum frumentaceum), on 'marva' (Eleushte indica), on 'ragi' (Eleusine coracana), on "bajra' (Pennisetum typhoideum), on 'baijanti' (Coix lachryma-jobi) and on 'juar' (Fletcher and Ghosh, 1920). (ii) This species has also been recorded in Ceylon, Indonesia, Iraq, Japan, Nyasaland and Taiwan (Jepson, 1954).

CONCLUSIONS We agree with Isaac and Venkatraman (1941) who pointed out that there are 4 ' spines' on each half of the cremaster of .the pupa, but disagree with Gupta (1960) who observed only 'two pointed projections' on each half in Chilotraea auricilia. Furthermore, Gupta's terminology " 1A' in the forewing of Crambid borers does not agree with the authors of wing venation. 1A is absent in the forewing of Crambids and the vein which Gupta termed as 1A is actually 2A. Our observations are based on the terminology adopted by Comstock (1960) and Brues, Melander and Carpenter (1954). The descriptions and drawings of the male genitalia of Chilo zonellus (now Chilo partellus) by Kinoshita and Kawada (1932) do not agree with our observations. The aedeagus of Chilo partellus is bifur- cate and the harpe is with a blunt process near the base of the costa. These characters were not observed by Kinoshita and Kawada. It is quite possible that they were dealing with another species altogether: Confusion has arisen regarding the synonymy of the names Chilo zonellus (Swinh.) and Chilo partellus (Swinh.). Hampson (1896) had shown that Crambus partellus Swinh. and Crambus zo,ellus Swinh. are synonyms of Chilo simplex Butl. But the last-named species is now considered as C. suppressalis. Whole mounts of caterpillars, wings and ~cr~italia of beth sexes of C. zonellus and C. partellus made by the authors show clearly that these two names are synonyms. This inference is in agreement with their position in regard to synonymy as stated by Bleszynski and Collins (1962). As these authors have shown that the specific name zonellus is already pre- occupied by Zeller's species z~m4lus first described under the genus Crambus in 1847, the name partellus would become valid. We agree with Kapur (1950) in his reasoning for erecting the genus Chilotraea on the basis of the shape of the frons and wing venation of the adult. Four Species of Paddy Stem Borers in Asia 191

A. KEY BASED ON THE ~V[ORPHOLOGY OF THE CATERPILLAR

Head* 1. Adfa very near to Adf2 ..... 2 Adfa almost midway between Adfl and Adf2 3 2. Pb on the line drawn on PI and P2 .... 4 Pb outside the line drawn on P1 and P2 • 5 3. Pb on the line drawn on PI and P2; Pa on the line drawn on P1 and L1 ; A2 longer (Fig. 16) • • • t • • • • • • • • • • Chilo partel/us (Swinhoe)

. Pa slightly below the line drawn on PI and L1 ; A2 longer (Fig. 15) ...... Chilo suppressalis (Walker)

. Pa slightly below the line drawn on P1 and L1; A2 minute (Fig. 14) ...... Chilotraea polychrysa (Meyrick) Pa almost on the line drawn on P1 and LI ; A2 shorter (Fig. 13) ...... Chilotraea auricilia (Dudgeon)

Body

1. Epsilon in A1 separate from rho; rho in A8 situated opposite to spiracle (Figs. 31 and 32) ...... 3 Epsilon in A1 either partly or wholly associated with rho; rho in A8 situated above and eephalad to the spiracle (Figs. 29 and 30) 2 2. Larva with five violet stripes, lateral stripes pass above abdominal spiracles (Figs. 5 and 6) • 4 3. Larva with four pinkish stripes, median stripe absent, lateral stripes pass above spiracles on abdominal segments (Fig. 8) 5

* On account of slight variations key for chaetotaxy of the head should be used in combi- nation with key for chaetotaxy of the body for separation of the species.

B4 i92 V.P. P,AO AND H. NAGARAJA

Larva with five distinct and complete and two indistinct and iucomplete stripes; lateral stripes pass on the spiracles of abdominal segments ; sublateral incomplete stripes pass on Kappa groups on abdominal segments (Fig. 7) ......

. Arrangement of crochets in complete circle. Tubercle-bearing Kappa group on T1 showing slight constriction in between kappa and eta (Fig. 18); epsilon wholly associated with rho in A1 (Fig. 26); lines drawn on setac alpha and beta on A8 converge caudad (Fig. 30) ...... Chilotraea polychrysa (Meyrick) Tubercle-bearing Kappa group on TI not showing constriction in between kappa and eta (Fig. 17); epsilon partly associated with rho in A1 (Fig. 25); lines drawn on setae alpha and beta on A8 converge cephalad (Fig. 29) - Chilotraea auricilia (Dudgeon) . Presence of asetose tubercle one in each of meso and metathorax in between them and Pi group and one asetose tubercle behind the spiracle in each of abdominal segments 1-7 inclusive (Figs. 24 and 28) Chilo partellus (Swinhoe) . Arrangement of crochets sometimes giving an appearance of incomplete circle due to sparsely arranged lateral crochets (Fig. 11); no asetose tubercles present on meso and metathorax and abdominal segments Chilo suppressalis (Walker)

B° KEY BASED ON PUPAL STRUCTURE . Frons produced, genae and thoracic spiracles slightly projected • 2 Frons not produced, genae and thoracic spiracles sharply projected ..... 3 Four Species of Paddy Stem-Borers in Asia 193 2. Frons more produced, genae not projecting; anterior region of the dorsum of 5th, 6th and 7th abdominal segments shagreened--without spines; eremaster with one or two pairs of setae and with only postero-lateral and postero-dorsal spines (Figs. 50 and 51) Chile suppressalis (Walker)

Frons less produced, genae slightly projecting; anterior region of the dorsum of 5th, 6th and 7th abdominal segments with minute intri- cately arranged spines sometimes giving an appearance of thick dGrsal spiny bands 4

. Spines distinct on the dorsum of 5th, 6th and 7th abdominal segments arranged almost in rows ...... 5

. Cremaster without setae and with 3 pairs of dorsal and one pair of ventral broad spines, all of equal size (Figs. 52 and 53) Chito partellus (Swinhoe)

. Postero-ventral spines are large and prominent, postero-lateral and postero-dorsal spines are smaller (Figs. 48 and 49) Chilotraea polychrysa (Meyrick)

Postero-dorsal and postero-lateral spines either more prominent or equal to the size of postero-ventral spines (Figs. 46 and 47) Chilotraea auricilia (Dudgeon)

C. KEY BASED ON WING VENATION

1. Forewing with Sc and RI fused together for some distance 2 Forewing with Sc and RI separate 4

2. Apices of fore and hindwings slightly acute; hindwing with inner margin normal • 3 194 V.P. RAo ANt) H. NAGARAJA

. Hindwing with M1 arising from Rs- on a short stalk after the anterior angle of the discoidal cell; M2 and M3 arising on a short common stalk (Fig. 58) ...... Chilotraea auricilia (Dudgeon) Hindwing with MI arising directly from Rs at the point of the anterior angle of the discoidal cell ; M2 and M3 arising on a long common stalk (Fig. 59) ..... Chilotraea polychrysa (Meyrick)

. Hindwing with M2 and M3 arising separately at the posterior angle of the discoidal cell 5 . Apices of the fore and hindwings rounded. Hindwing with inner margin enlarged; M1 arising from Rs on a long stalk after the anterior angle of the discoidal cell; basal areole enlarged (Fig. 60) Chile supl)ressalis (Walker) Apices of the forewing sharply acute and hind- wing slightly acute. Hindwing with inner margin not enlarged; M1 arising from Rs before the anterior angle of the discoidal cell ; basal areole normal (Fig. 61) Chile partellus (Swinhoe)

D. KEY BASED ON GENITALIA Male Genitalia I. Aedeagus bifurcate ...... 2 Aedeagus trifurcate ...... 3 . Upper limb with ventral triangular keel in the middle ...... 4 Upper limb not sharply pointed, without a ventral triangular keel in the middle 5 Upper limb with the apex pointed and a pointed projection dorsally in the middle, lower limb tongue-like, the apex bifid; harpe Four Species of Paddy Stem-Borers in Asia 195

subquadrate; anellus with median mem- branous plate with sclerotized blunt lateral projections ; vinculum narrow, triangular (Figs. 62, 66 and 68) ...... Chilotraea auricilia (Dudgeon)

. Upper limb of the aedeagus pointed at the tip and swollen in the middle, lower two limbs U-shaped with blunt slightly dilated tips with cornuti; harpe triangular with broad base; anellus highly chitinized, crescent- shaped; vinculum with truncated base (Figs. 63, 67 and 69) ...... Chilotraeapotyehrvsa (Meyriek)

. Harpe with a blunt projection near the base of the costa ; anellus with almost triangular chiti- nized median plate with long lateral processes ; vinculum broadly triangular (Figs. 65 and 75) ...... Chile partellus (Swinhoe)

. Harpe withoutprojection near base of the costa; anellus without a median plate, the lateral arms enlarged each with two lobes, the inner lobe drawn into a long blunt process beneath aedeagus; vinculum more U-shaped (Figs. 64 and 74). • • "...... Chile suppressalis (Walker)

Female Genitalia

1. Signum present ...... Signum absent ...... 2. Lamella antevaginalis very distinct, broad and longitudinally wrinkled with bitid apex; lamella postvaginalis not distinct; signum small, bursa copulatrix comparatively long and capitate (Fig. 81) ~ ..... Chile partellus (Swinhoe~ 196 V. P. RAO AND H. NAGARAJA Lamella antevaginalis not distinct, in the form of semicircular poorly ehitinized area above ostium bursae; lamella postvaginalis indis- tinct and with very indistinct wrinkles; signum large and prominent consisting of hook-like sclerotized minute bodies • 4

. Lamella antevaginalis distinct but very small, broader than long in the form of elevated sclerite; lamella postvaginalis indistinct; bursa eopulatrix elavate, base of duet-us bursae sclerotized (Fig. 79) ...... Chilotraea polychrysa 0Vleyriek)

Lamella antevaginalis distinct in the form of ~micircular wrinkled sclerite surrounding the ostium bursae anteriorly; lamella post- vaginalis distinct but narrow; bursa eopu- latrix slightly eapitate (Fig. 78) ..... Chilotraea aurieilia (Dudgeon)

. Duetus bursae enlarged, uniformly thinly sclero- tized with longitudinal wrinkles; the region between enlarged duetus bursae and eorpus bursae narrow and slender; corpus bursae clavate (Fig. 80) ...... Chile suppressalis (Walker)

SUMMARY

A comparative account of the tarval chaetotaxy, pupal structure, venation and genitalia of moths of four species of striped borers belonging to the genera Chilotraea and Chile (Lepidoptera: Pyralidae: Crambinae) attacking paddy in ,Asia is given in detail. The species dealt with are Chilotraea auricilia fDdgn.), C. polychrysa (Meyr.), Chile suppressalis IWalk.) and C. partellus (Swinh.). Four tabular statements and four keys showing the differences in the chaetotaxy of the borers, pupal structure, wing venation and genital structures are also included to facilitate the accurate delermina, tion of these species. Four Species of Paddy Stem-Borers in Asia 197

REFERENCES

Bleszynski, S. and Collins, "A short catalogue of the World species of the family R.J. (Lepidoptera),"/teta Zool. Crae., 1962, 7(12), 238-46. Brues, C. T., Melander, A. L. "Classification of insects," Bull. Mus. comp. Zool., and Carpenter, F. M. Harvard College, 1954, 108, 243-45.

Butani, D. K. .. "A key for the identification of sugarcane borers," Indian J. Ent., 1956, 18 (3), 302--04.

Comstock, J.H. .. /In Introduction to Entomology (Ninth Revised Edition), Comstock Publishing Associates, Ithaca, Hew York, 1960, 644-52.

----- and Needham, J. G... "The wings of insects," Amer. Nat., 1898-99, 32, 43-48, 81-89, 231-57, 413-22, 560-65, 769-79, 903-11 ; 33, 117-26, 573-82, 845-60.

Dudgeon, G. C. .. "Descriptions of new species of moths from India and Burma," J. Bombay nat. Hist. Sot., 1905, 16, 405.

Fletcher, T. B. .. "Report of the Imperial Entomologist," ScL Rep. Agric. Res. Inst., Pusa, for 1926-27, 1928, 57-60.

- and Ghosh, C. C. •. "Borers in sugarcane, rice, etc.," Rept. Proc. Third ent. Meet., Pusa, 1920, 354--417.

Fraeker, S. B. .. "The classification of Lepidopterous larvae," Illinois biol. Monog., 1915, 2(1), 81-89.

Ghosh, C. C. •. "Supplementary observations on borers in sugarcane, rice, etc.," Rept. Proe. Fourth ent. Meet., Pasa, 1921, 114-27.

Gupta, B. D. •. "The anatomy, life and seasonal history of striped moth-borers of sugarcane in North Bihar and West United Provinces," Indian J. agrie. ScL, 1938, 10, 787-817.

•. "Identification of the striped moth-borers of sugarcane in India,'" Indian Inst. Sugarcane Res. Technical Bull., 1960, No. 1, pp. 10.

Hampson, G.F. .. Fauna of British India, Moths, 1896, 4, 26-28.

Isaac, P.V. and Rao, K. V... "A key for the identification of the larvae of the known Lepidop- terous borers of sugarcane in India based on morphological characters," Indian J. agric. Sci., 1941, 11 (5), 795-803.

and Venkatraman, "A key for the identification of the pupae of the known Lepidop- T.V. terous borers of sugarcane in India, based on morphological characters,"/bid., 1941, 11 (5), 804-15.

$epson, W. F. ... A Critical Review of the World Literature on the Lepidopterous Stalk Borers of Tropical Graminacious Crops, Commonw. ~[nst. Ent., London, 1954, 8-32. 198 V. P. RAO AND H. NAGARAJA

Kaput, A. P. .. "The identity of some Crambinae associated with sugarcane in India and of certain species related to them-(Lepidoptera: Pyralidae)," Trans. R. ent. Soc., London, 1950, 101(11), 389-434. Kinoshita, S. and Kawada, A. ~'A revision of rice borers (Chilo) and their distribution (Resume)," J. Imp. agric. Exp. Sta., Japan, 1932, 2 (1), 97-104. * Meyrick, E. .. Exotic Microlepidoptera, Marlborough, 1932, 4, 321. Nair, M. G. R.K. .. "The biology and control of a rice stalk borer, Proceras poly- chrysa (M.) (Lepidoptera: Pyralidae) from Kerala," Indian J. Ent., 1958, 20(2), 136-42. Peterson, A. Larvae of Insects, an Introduction to Nearctic Species : Part I. Lepidoptera and Plant Infesting Hymenoptera, Columbus, Ohio, 1959, 60-236. *Swinhoe, C. "On the Lepidoptera of Bombay and the Deccan, Part IV. Heterocera," Proc. zool. Soc., London, 1885, 852-886. Torre-Bueno, J.R. de . .. A Glossary of Entomology (Second Printing), Brooklyn Ent. Sot., Brooklyn, New York, 1950, 336pp. Trehan, K. N. and Butani, "Systematic position of ChUo zonellus Swinhoe and chaetotaxy D.K. of its larvae," Indian J. agric. Sci., 1948, 20 (1), 79-85. Tuxen, S. L. .. Taxonomist's Glossary of Genitalia in Insects, Ejnar Munksgaard, Copenhagen, 1956, 97-110. *Walker, F. •. List of the Specimens of the Lepidopterous Insects in the Collection of the British Museum. Pt. 27, Crambites and Tortricites, London, 1863, 144. Zimmerman, E. C. Insects of Hawaii, Lepidoptera, , University of Hawaii Press, Honolulu, 1958, 8, 277-342.

* Originals not seen.

EXPLANATION OF TEXT-FIGURES

FIGS. 1-4. Fig. 1. Dorsal view of the full-grown caterpillar of Chilotraea auricilia (Dudgeon), × 8. Fig. 2. Dorsal view of the full-grown caterpillar of Chilotraea polychrysa (Meyrick), × 8. Fig. 3. Dorsal view of the full-grown caterpillar of Chilo suppressalis.(Walker), x6½. Fig. 4. Dorsal view of the full-grown caterpillar of Chilo partellus (Swinhoe), x6{. dins., dorso-median stripe; sds., sub-dorsal stripe; Is., lateral stripe; inc. sis., incomplete sublateral stripe. Fins. 5-8. Fig. 5. Diagrammatic sketch showing the position of stripes on the 1st abdominal segment of Chilotraea aaricilia (Dudgeon), x 28. Fig: 6. Diagrammatic sketch showing the position of stripes on the 1st abdominal segment of Chilotraeapolychrysa (Meyrick), ×32. Fig. 7. Diagrammatic sketch showing the position of stripes on the 1st abdominal segment of Chilo suppressalis (Walker), x 24. Fig. 8. Diagrammatic sketch showing the position of stripes on the 1st abdominal segment of Chilo partellus (Swinhoe), x24. dins., dorso-median stripe; sds., sub-dorsal stripe; ls., lateral stripe; inc. sls., incomplete sub-lateral stripe. Four Species of Paddy Stem Borers in Asia 199

FIGS. 9-12. Fig. 9. Arrangement of crochets on the 1st abdominal proleg of Chilotraea auricilia (Dudgeon), x 120. Fig. 10. Arrangement of crochets on the 1st abdominal proleg of Chilotraea polychrysa (Meyrick), x 12. Fig. 11. Arrangement of crochets on the 1st abdominal proleg of Chilo suppressalis (Walker)× 110. Fig. 12. Arrangement of crochets on the 1st abdo- minal proleg of Chilo partellus (Swinhoe), x75.

FIGs. 13-16. Fig. 13. Chaetotaxy of the head of Chilotraea aurieilia (Dudgeon), x30. Fig. 14. Chaetotax'y of the head of Chilotraea polychrysa (Meyrick), x30. Fig. 15. Chaetotaxy of the head of Chile suppressalis (Walker), ×30. Fig. 16. Chaetotaxy of the head of Chile partellus (Swinhoe), x30. A., anterior; Adf, adfrontal; E., epistomial; F., frontal; M., median; L., lateral; LI., lateral (labrum); O., ocellar; P., posterior; Up., ultra-posterior. (Alphabets in capitals followed by number indicate seta ; alphabets followed by small letter indicate puncture).

FIGS. 17-20. Fig. 17. Camera lucida sketch showing the arrangement of setae on the 1st thoracic segment of Chilotraea auricilia (Dudgeon), x 35. Fig. 18. Camera lucida sketch showing the arrangement of setae on the 1st thoracic segment of Chilotraeapolychrysa (Meyrick),x35. Fig. 19. Camera lucida sketch showing the arrangement of setae on the 1st thoracic segment of Chile suppressalis (Walker), x35. Fig. 20. Camera lucida sketch showing the arrangement of setae on the 1st thoracic segment of Chile partellus (Swinhoe), x35. a, alpha; ~, beta; y, gamma; 8, delta; ~, epsilon; p, the; K, kappa; 7, eta; v, nu; ~r, pie; or, sigma.

FIGs. 21-24. Fig. 21. Camera lucida sketch showing the arrangement of setae on 2nd thoracic segment of Chilotraea auricilia (Dudgeon), x 35. Fig. 22. Camera lucida sketch showing the arrangement of setae on 2nd thoracic segment of Chilotraea polychrysa (Meyrick), x 35. Fig. 23. Camera lucida sketch showing the arrangement of setae on 2nd thoracic segment of Chile suppressalis (Walker), x 28. Fig. 24. Camera lucida sketch showing the arrangement of setae on 2rid thoracic segment of Chilo~partellus (Swinhoe), x 26. a, alpha; /3, beta; p, rho; E, epsilon; 0, theta; x, kappa; 71, eta; v, nu; ~r, pi; a, sigma; at, asetose tubercle.

Fins. 25-28. Fig. 25. Camera lucida sketch showing the arrangement of setae on the 1st abdominal segment of Chilotraea auricilia (Dudgeon), x 35. Fig. 26. Camera lucida sketch showing the arrangement of setae on the 1st abdominal segment of Chilotraea polychrysa (Meyrick), × 35. Fig. 27. Camera lucida sketch showing the arrangement of setae on the 1st abdominal segment of Chile suppressalis (Walker), x 26. Fig. 28. Camera lucida sketch showing the arrangement of setae on the i st abdominal segment of Chile partellus (Swinhoe), × 28. •, alpha; /~, beta; p, the; ~, epsilon; x. kappa; */, eta; /~, mu; ~, nu; ~r, pi; ~, tau; tr, sigma; at, asetose tubercle.

FIGS. 29-32. Fig. 29. Camera lucida sketch showing the arrangement of setae on the 8th abdominal segment of Chilotraea auricilia (Dudgeon), x 35. Fig. 30. Camera lueida sketch showing the arrangement of setae on the 8th abdominal segment of Chilotraea polychrysa (Meyrick), x 35. Fig. 31. Camera lucida sketch showing the arrangement of setae on the 200 V.P. RAO AND H. NAGARAJA

8th abdominal segment of Chilo suppressalis (Walker), × 26. Fig. 32. Camera lucida sketch showing the arrangement of setae on the 8th abdominal segment of Chilo partellus (Swinhoe)~ × 28. a, alpha; 3, beta; p, rho; ~, epsilon; ~, kappa; I/, eta; /~, mu; ~r, pi; c,, sigma.

FIGS. 33-40. Fig. 33. Lateral view of pupa of Chilotraea auricilia (Dudgeon), × 9. Fig. 34. Lateral view of pupa of Chilotraea polychrysa (Meyrick), × 9. Fig. 35. Lateral view of pupa of Chilo suppressalis (Walker), ×7½. Fig. 36. Lateral view of pupa of Chilopartellus (Swinhoe), xT½. Fig. 37. Arrangement of spines on the dorsum of 5th abdominal segment of the pupa of Chilotraea auricilia (Dudgeon), ×37½. Fig. 38. Arrangement of spines on the dorsum of 5th abdominal segment of the pupa of Chilotraea polyehrysa (Meyrick), × 37½. Fig. 39. Arrangement of spines on the dorsum of 5th abdominal segment of the pupa of Chilo suppressalis (Walker), ×37½. F~. 40. Arrangement of spines onthe dorsum of 5th abdominal ~gment of the pupa of Chilo partellus (Swinhoe), × 37½. /., frons; g., gena.

FIGs. 41.-45. Fig. 41. Postero-ventral region of the pupa of Chilotraea auricilia (Dudgeon), x 22. Fig. 42. Postero-ventral region of the pupa of Chilotraea polychrysa (Meyrick), ×22. Fig. 43. Postero-lateral region of the pupa of Chilo suppressalis (Walker), × 21. Fig. 44. Postero-ventral region of the pupa of Chilo suppressalis (Walker), × 22. Fig. 45. Postero- ventral region of the pupa of Chilo partellus (Swinhoe), × 22. s., seta.

Flos. 46-53. Figs. 46 and 47. Dorsal and ventral views of the cremaster of the pupa of Chilotraea auridlia (Dudgeon), × 45. Figs. 48 and 49. Dorsal and ventral views of the ere- master of the pupa of ChlTotraea polyehrysa (Meyrick), × 45. Figs. 50 and 51. Dorsal and ventral views of the cremaster of the pupa of Chilo suppressalis (Walker), × 45. Figs. 52 and 53. Dorsal and ventral views of the cremaster of the pupa of Chilo partellus (Swinhoe), × 45. pd., postero-dorsal spine; pl., postero-lateral spine; pv., postero-ventral spine; s., seta.

FIGS. 54-57. Fig. 54. Forewing of Chilotraea aurieilia (Dudgeon), .'< 8. Fig. 55. Fore- wing of Chilotraea polychrysa (Meyrick), × 8. Fig. 56. Forewing of Chilo suppressalis (Walker), × 8. Fig. 57. Forewing of Chilo partellus (Swinhoe), × 8. A., Anal; Cu., Cubitus; M., Media; R., Radius; Se., Subcosta; D., Discoidal cell.

Fins. 58-61. Fig. 58. Hindwing of Chilotraea auricilia (Dudgeon), × 8. Fig. 59. Hindwing of Chilotraea polychrysa (Meyrick), × 8. Fig. 60. Hindwing of Chilo suppressalis (Walker), x 8. Fig. 61. Hindwing of Chilo partellus (Swinhoe), × 8. A., Anal; ba., basal arcole; D., Discoidal cell; Cu., Cubitus; M., Media; Rs., Radial sector; S¢ -t- M-Subcosta -t- first Radial vein.

FIGs. 62-65. Fig. 62. Male genitalia of Chilotraea auricilia (Dudgeon), × 36. Fig. 63. Male genitalia of Chilotraea polychrysa (Meyrick), x 36. Fig. 64. Male genitalia of Chllo • uppressalis (Walker), x 24. Fig. 65. Male genitalia of Chilo parteUus (Swinhoe), x 30, h,, harpe; v., vincuhan. Four Species of Paddy Stem-Borers in Asia 201

FIos. 66-77. Fig. 66. Aedeagus of Chilotraea auricllia (Dudgeon), x 66. Fig. 67. Aedeagus of Chilotraea polyehrysa (Meyriek), x 53. Fig. 68. Anellus of Chilotraea auricilia (Dudgeon), x 66. Fig. 69. Anellus of Chilotraea polychrysa (Meyrick), x 53. Fig. 70. Position of aedeagus and anellus in Chilotraea aurieilia (Dudgeon), x 66. Fig. 71. Position of aedeagus and anellus in Chilotraea polychrysa (Meyrick), z 53. Fig. 72. Aedeagus of Chilo suppressalis (Walker), x 33. Fig. 73. Aedeagus of Chilo partellus ($winhoe), × 40. Fig. 74. Anellus of Chilo suppressalis (Walker), x 33. Fig. 75. Anellus of Chilo partellus (Swinhoe), x40. Fig. 76. Positionof aedeagusand anellusin Chilo suppressalis (Walker), x 33. Fig. 77. Position of aedeagus and anellus in Chilo t~arteUus (Swinhoe), x 40.

FIGs. 78-81. Fig. 78. Female genitalia of Chilotraea aurlcilia (Dudgeon), x 24. Fig. 79. Female genitalia of Chilotraea polyehrysa (Meyriek), x 24. Fig. 80. Female genitalia of Chilo suppressalis (Walker), x 24. Fig. 81. Female genitalia of Chilo partellus (Swinhoe), ,-<24. apo-ant., apophysis anterior; apo.p., apophysis posterior; crp.bu., corpus bursae; du.bu., ductus bursae; Ila., lamella antevaginalis; ilp., lamella postvaginalis; o.b., ostium bursae; s/g., signum. 202 V.P. RAo AND 1-]. NAGARAffA

4 F~Gs. I-4 Four Species of Paddy Stem-Borers in Asia 203

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